KR100589685B1 - A membrane separation apparatus for processing foul water and a cleaning method thereof - Google Patents

Abstract

The present invention relates to a membrane separation device for sewage treatment and a cleaning method of such a membrane separation device, and in particular, the permeate pressure of the membrane module installed in the membrane separation device is automatically measured so that the permeation pressure of the membrane is constant. The present invention relates to a membrane separation apparatus for sewage treatment that can easily and automatically clean the membrane module using air bubble fluctuations and ultrasonic waves, and a method for cleaning such membrane separation apparatus. The membrane separation apparatus for sewage treatment according to the present invention includes a reaction tank, an inflow pump for introducing sewage into the reaction tank, a membrane module installed inside the reactor, and a membrane module connected to the reaction tank by the inflow pump. A suction pump for discharging the introduced sewage through the membrane module, an air purifier mounted on the bottom of the reaction tank for supplying air to the activated sludge introduced into the reaction tank, and first air for supplying air to the air purifier A pump, a plurality of diffusers mounted at the bottom of the membrane module to clean the membrane module, a second air pump to supply air to the plurality of diffusers, and a plurality of ultrasonic waves to clean the membrane module. Device.

Description

Membrane Separation Apparatus for Cleaning Sewage and Methods for Cleaning Such Membrane Separation Apparatus {A MEMBRANE SEPARATION APPARATUS FOR PROCESSING FOUL WATER AND A CLEANING METHOD THEREOF}

1 is a process configuration flowchart of a general sewage treatment method.

2 is a process configuration flowchart of a conventional membrane separation method.

3 is a schematic view of a membrane separation apparatus for sewage treatment according to an embodiment of the present invention.

4 is a view showing the diffuser and the ultrasonic generator of the membrane separation device for sewage treatment according to an embodiment of the present invention.

5 is a flow chart of the cleaning method of the membrane separation apparatus for sewage treatment according to an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

1: reactor 2: membrane module

3: ultrasonic generator 4: diffuser

5: control device 6: heating device

7: stirrer 8: acidifier

9: inflow pump 10: suction pump

11, 11a: air pump

The present invention relates to a membrane separation device for sewage treatment and a cleaning method of such a membrane separation device, and in particular, the permeate pressure of the membrane module installed in the membrane separation device is automatically measured so that the permeation pressure of the membrane is constant. The present invention relates to a membrane separation apparatus for sewage treatment that can easily and automatically clean the membrane module using air bubble fluctuations and ultrasonic waves, and a method for cleaning such membrane separation apparatus.

As shown in FIG. 1, the activated sludge method, which is generally used to treat domestic sewage, is composed of a sedimentation tank ⇒ a screen ⇒ a flow rate adjustment tank ⇒ a primary sedimentation tank ⇒ an activated sludge reaction tank ⇒ a secondary sedimentation tank ⇒ a disinfection tank. However, such activated sludge process has a complicated process configuration, and the treatment effect fluctuates seasonally due to the influence of temperature, and also greatly affects the treatment water quality due to the bulking phenomenon of microorganisms in the reactor. In addition, since it is mainly applied to a large-capacity treatment facility, it is difficult to maintain and require constant management by professional personnel.

Therefore, in order to solve this problem, a membrane separation device or membrane separation process for sewage treatment, which can be utilized in small-scale and advanced treatment facilities by immersing a separator (or membrane) in a reaction tank (or aeration tank), has been introduced. .

Figure 2 shows a process diagram of a conventional membrane separation method. Reference numeral 21 denotes a screen process, 22 denotes a flow control tank, 23 denotes a submersible pump, 24 denotes a reaction tank (or aeration tank), 25 denotes an aerator, 26 denotes a separator, 27 denotes a blower, and 28 denote a suction pump. .

However, such a conventional submerged membrane separation apparatus or process has a large amount of suspended solids (SS) and microbial metabolites or biofilms on the surface of the membrane when the membrane immersed in the reaction tank into which the activated sludge is put to long operation. It is a common phenomenon that the filtration performance of the separator is lowered due to adhesion. That is, the permeate flux (permeate flux) is reduced, the permeate pressure (permeate pressure) results in an increase, ultimately reaching a state in which normal operation is impossible, it takes a lot of power.

The air bubbling method using air bubbles is a method used as a means to reduce the contamination of the separator and to increase the operation period as much as possible. Air bubble cleaning method is to install the diffuser at the bottom of the reaction vessel equipped with a separator, suspended solids (SS) or microbial membrane (S) accumulated on the surface of the membrane by using the lifting force of the air bubble is supplied from the pressurized air pump (blower) ( It has been a problem in the field application in that there is a limitation in the method of removing the biofilm and the complete control of the original contamination of the membrane, and there is a problem that the cycle of membrane contamination and clogging becomes faster during unstable cleaning. .

Therefore, there is a need for a new type of membrane separation apparatus or a method for cleaning the membrane, which can solve the problems of the conventional membrane separation apparatus or the process of cleaning the membrane.

An object of the present invention is to automatically measure the permeate pressure of the membrane module installed in the membrane separation device (membrane module easily and automatically using air bubble fluctuations and ultrasonic waves when the permeate pressure of the membrane falls below a certain level) It is to provide a membrane separation device for sewage treatment that can be cleaned and a cleaning method of such a membrane separation device.

An object of the present invention is the membrane module is connected to the reaction tank, the inlet pump for introducing the sewage into the reaction tank, the membrane module is installed inside the reactor, and the membrane module is connected to the membrane module sewage introduced into the reaction tank by the inlet pump A suction pump discharged through the air, an air purifier installed at the bottom of the reaction tank for supplying air to the activated sludge introduced into the reaction tank, and a first air pump for supplying air to the air purifier, and the membrane module. A sewage treatment including a plurality of diffusers mounted at a lower end and a second air pump for supplying air to the plurality of diffusers, respectively, and a plurality of ultrasonic generators for cleaning the membrane module. By means of a membrane separation device.

Preferably, the plurality of ultrasonic wave generators are alternately arranged with a plurality of diffusers mounted under the membrane module.

Membrane separation apparatus for sewage treatment according to the present invention is a control device connected to the inflow pump, the suction pump, the first and second air pump and the plurality of ultrasonic generators, respectively, the flow rate flowing through the suction pump When the permeate pressure of the membrane module rises to a predetermined level or more, the operation of the inflow pump, the suction pump, and the first air pump is stopped, and the second air is used to clean the membrane module. The control apparatus may further include a control device configured to operate a pump to inject air into the plurality of diffusers and operate the plurality of ultrasonic wave generators.

The control device detects the flow rate flowing out through the suction pump, and when the permeation pressure of the membrane module falls below a predetermined level, the operation of the second air pump and the ultrasonic generator is stopped, and the inflow pump and the suction pump are stopped. And operating the first air pump again.

Membrane separation apparatus for sewage treatment according to the present invention is a heating device connected to the control device to increase the temperature of the sewage flowed into the reactor in order to increase the efficiency of cleaning during the cleaning of the membrane module by the control device A height heating device; Preferably, the stirrer may further include a stirrer for stirring the activated sludge to prevent anaerobic activation of activated sludge introduced into the reactor during the cleaning of the membrane module by the controller as the stirrer connected to the control device.

It is also an object of the present invention, the inlet pump for introducing sewage into the reaction tank, the membrane module is installed inside the reactor, and the sewage introduced into the reaction tank by the inlet pump connected to the membrane module A suction pump discharged through the membrane module, an air purifier mounted on the bottom of the reaction tank for supplying air to the activated sludge introduced into the reaction tank, and a first air pump for supplying air to the air purifier; Sewage treatment including a plurality of diffusers mounted on the bottom of the module for cleaning the membrane module, a second air pump for supplying air to the plurality of diffusers, respectively, and a plurality of ultrasonic generators for cleaning the membrane module A method of cleaning a membrane separation device for measuring the flow rate through the suction pump Comparing the permeation pressure of the membrane module with a preset value, and when the permeation pressure of the membrane module is greater than or equal to the preset value in the comparing step, operating the inflow pump, the suction pump, and the first air pump. Stopping the membrane, and operating the second air pump to clean the membrane module, injecting air into the plurality of diffusers and operating the plurality of ultrasonic generators. It is achieved by the washing method of.

The cleaning method of the membrane separation apparatus for sewage treatment according to the present invention comprises the steps of raising the temperature of the sewage introduced into the reactor to increase the efficiency of cleaning while the membrane module is being cleaned, and the membrane module is cleaned It is preferable to further include the step of stirring the activated sludge in order to prevent the anaerobic activation of the activated sludge introduced into the reactor.

In addition, the cleaning method of the membrane separation apparatus for sewage treatment according to the present invention by measuring the flow rate flowing through the suction pump while the membrane module is cleaned by the diffuser and the ultrasonic wave generator of the membrane module When the permeation pressure of the membrane module is restored to the preset value or less by comparing the permeation pressure with a preset value, the operation of the second air pump, the ultrasonic generator, the heating device and the stirrer is stopped, and the inflow pump and the The suction pump and the first air pump are operated again.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments will now be described in detail with reference to the accompanying drawings as examples only.

Figure 3 schematically shows a membrane separation device for sewage treatment according to an embodiment of the present invention. As can be seen from Figure 3, the membrane separation apparatus for sewage treatment according to an embodiment of the present invention is a reaction tank (1), inflow pump (9) for introducing the sewage into the reaction tank (1), inside the reaction tank (1) Intake pump 10, a reaction tank connected to the membrane module 2, the membrane module (2) installed in the discharged sewage flowing into the reaction tank 1 by the inflow pump 9 through the membrane module (2) ( 1) an air purifier (8) mounted at the bottom of the reactor (1), a first air pump (11a) for supplying air to the air purifier (8), and a membrane module (2) for supplying air to activated sludge introduced into the tank 1 A plurality of diffusers 4 for cleaning the membrane module 2, a second air pump 11 for supplying air to the plurality of diffusers, and a plurality of diffusers for cleaning the membrane module 2. Ultrasonic generator (3), heating device (6), reactor (1) used for temperature control of sewage flowing into reactor (1) It consists of a stirrer 7 and a control device 5 for stirring the activated sludge in order to prevent the anaerobicization of the activated sludge to be added to.

As shown in FIG. 3, the control device 5 includes a plurality of diffusers 4 and a plurality of ultrasonic generators 3 (for convenience, one diffuser 4 and one ultrasonic generator respectively in FIG. 3). Control device 5 connected to (3)}, heating device 6, stirrer 7, inlet pump 9, suction pump 10, first air pump 11a and second air Respectively connected to the pump 11.

4 is an enlarged view of a plurality of diffusers 4 and a plurality of ultrasonic wave generators 3 mounted below the membrane module 2. As shown, it can be seen that the diffuser 4 and the ultrasonic generator 3 are alternately arranged to increase the cleaning efficiency of the membrane module 2.

Now, the cleaning mechanism of the membrane module of the membrane separation device for sewage treatment according to an embodiment of the present invention by the control device 5 will be described.

The control device 5 detects the flow rate of the sewage flowing out through the suction pump 10 to detect the permeation pressure of the membrane module 2. When the permeation pressure of the membrane module 2 detected in this way rises above a certain level, the control device 5 supplies a first air pump for supplying air to the inflow pump 9, the suction pump 10, and the air purifier 8. The operation of 11a is stopped. The control device 5 then operates the second air pump 11 to inject air into the plurality of diffusers 4 and to operate the plurality of ultrasonic generators 3. In this way, the cleaning operation | movement of the membrane module 2 in which permeation pressure was raised by the diffuser engine 4 and the ultrasonic wave generator 3 which are operated by the control apparatus 5 is performed.

In particular, the ultrasonic wave generated by the ultrasonic generator 3 penetrates to a minute part and can be precisely cleaned, but does not damage the object to be cleaned. In addition, there is an advantage that the cleaning efficiency can be doubled by cleaning the membrane module 2 whose permeation pressure is increased by ultrasonic waves generated by the ultrasonic generator 3 together with the air flowing out of the diffuser 4.

In order to maximize the cleaning efficiency while the membrane module 2 is cleaned by the diffuser 4 and the ultrasonic generator 3, the control device 5 operates a heating device 6 connected to the control device 5. The control device 5 controls to increase the temperature of the sewage and to prevent the anaerobic activation of activated sludge introduced into the reactor 1 which is precipitated under the diffuser 4 and the ultrasonic generator 3 during the cleaning. Activated sludge is agitated through an agitator 7 connected to the apparatus 5.

While the membrane module 2 is cleaned, the control device 5 temporarily operates the suction pump 10 to detect ghosts flowing out through the suction pump 10 to periodically detect the permeation pressure of the membrane module 2. Done. If the control device 5 detects that the membrane module 2 is sufficiently cleaned and the permeation pressure of the membrane module 2 has dropped below a certain level, the control device includes the second air pump 11 and the ultrasonic generator. The operation of (3) is stopped and the inflow pump 9, the suction pump 10 and the first air pump 11a are operated again. In this process, the control device 5 may stop the heating device 6 and the stirrer 7.

Now, a cleaning method of a membrane separation apparatus for sewage treatment according to an embodiment of the present invention will be described with reference to FIG. 5.

Starting in step S1, in step S2 the permeation pressure of the membrane module 2 is compared with a preset value. If in step S2 the permeation pressure of the membrane module 2 is found to be below the set value, the sewage treatment operation of the membrane separation device is continued. If the permeation pressure of the membrane module 2 is found to be above the set value, In step S3, the operation of the inflow pump 9, the suction pump 10 and the first air pump 11a is stopped. Subsequently, the second air pump 11 and the ultrasonic generator 3 are operated to clean the membrane module 2 in step S4, and the heating device 6 and the stirrer are operated in steps S5 and S6. (7) is activated.

In this way, after some cleaning of the membrane module 2, the permeation pressure of the membrane module 2 is again compared with the set value in step S7. If it is determined that the permeation pressure is greater than or equal to the set value, step S7 is transferred to step S3. If it is determined that the permeation pressure is less than or equal to the set value, step S7 is transferred to step S8 to determine the second air pump ( 11), the operation of the ultrasonic generator 3, the heating device 6 and the stirrer 7 is stopped. Then, in order to perform the sewage treatment again, the operation of the inflow pump 9, the suction pump 10 and the first air pump 11a is restarted in step S9.

So far, a preferred embodiment of the present invention has been described. However, the embodiments described so far should only be taken as examples. That is, those skilled in the art will be able to derive various modifications with reference to the preferred embodiment of the present invention. Accordingly, the technical scope of the present invention should be interpreted only by the appended claims.

As described above, the present invention is a water treatment device that combines the membrane and the ultrasonic cleaning device can be obtained a purification method using a high concentration of activated sludge in the aeration tank and excellent treated water through membrane separation of the membrane, the separate cleaning for cleaning the membrane Without the need for tanks, the aeration tank can be minimized by the air bubble oscillator and the ultrasonic cleaning device, and the entire reaction response volume can be minimized.

Claims (11)

delete As membrane separation device for sewage treatment, Reactor, An inflow pump for introducing sewage into the reactor; A membrane module installed inside the reactor, A suction pump connected to the membrane module and discharging sewage introduced into the reaction tank by the inflow pump through the membrane module; An air purifier installed at the bottom of the reactor for supplying air to the activated sludge introduced into the reactor and a first air pump for supplying air to the acid generator; A second air pump mounted at a lower end of the membrane module to supply air to the plurality of diffusers and the plurality of diffusers, respectively, for cleaning the membrane module; A plurality of ultrasonic generators for cleaning the membrane module, characterized in that it comprises an ultrasonic generator disposed alternately with a plurality of diffusers mounted on the membrane module, Membrane separator for sewage treatment. The membrane module of claim 2, wherein the inlet pump, the suction pump, the first and second air pumps, and a plurality of ultrasonic generators are respectively connected to each other to detect the flow rate flowing through the suction pump. When the permeate pressure rises above a predetermined level, the operation of the inflow pump, the suction pump and the first air pump is stopped, and the second air pump is operated to clean the membrane module. Membrane separation apparatus for sewage treatment, characterized in that it further comprises a control device for injecting air to the diffuser of the operation of the plurality of ultrasonic generators.  The method of claim 3, wherein the control unit, by detecting the flow rate flowing through the suction pump to lower the permeation pressure of the membrane module below a predetermined level, the operation of the second air pump and the ultrasonic generator stops and Membrane separation apparatus for sewage treatment, characterized in that for operating the inlet pump, the suction pump and the first air pump. 5. The heating apparatus according to claim 4, further comprising a heating apparatus connected to the control apparatus, wherein the heating apparatus increases the temperature of the sewage introduced into the reactor to increase the efficiency of cleaning during the cleaning of the membrane module by the control apparatus. Membrane separation apparatus for sewage treatment, characterized in that. The stirrer according to claim 5, wherein the stirrer is connected to the control device, and the stirrer for stirring the activated sludge in order to prevent anaerobic activation of activated sludge introduced into the reactor during the cleaning of the membrane module by the control device. Membrane separation apparatus for sewage treatment, further comprising. delete Suction tank, an inlet pump for introducing sewage into the reactor, a membrane module installed inside the reactor, and a suction coupled to the membrane module to discharge the sewage introduced into the reactor by the inflow pump through the membrane module. A pump, an air purifier installed at the bottom of the reactor for supplying air to the activated sludge introduced into the reactor, a first air pump for supplying air to the air purifier, and mounted at a lower end of the membrane module, Cleaning of the membrane separation apparatus for sewage treatment, comprising a plurality of diffusers for cleaning the membrane module, a second air pump for supplying air to the plurality of diffusers, respectively, and a plurality of ultrasonic generators for cleaning the membrane module As a method, Measuring the flow rate flowing through the suction pump and comparing the permeation pressure of the membrane module with a preset value;  Stopping the operation of the inflow pump, the suction pump and the first air pump when the permeation pressure of the membrane module is greater than or equal to the preset value in the comparing step; Operating the second air pump to inject air into the plurality of diffusers and to operate the plurality of ultrasonic wave generators to clean the membrane module; It characterized in that it comprises the step of increasing the temperature of the sewage introduced into the reactor to increase the efficiency of the cleaning during the cleaning of the membrane module, Method for cleaning membrane separation device for sewage treatment. The method of claim 8, further comprising the step of stirring the activated sludge in order to prevent the anaerobic activation of activated sludge introduced into the reactor during the cleaning of the membrane module, membrane separation for sewage treatment Method of cleaning the device. 10. The method of claim 9, wherein while the membrane module is cleaned by the diffuser and the ultrasonic wave generator, the flow rate flowing through the suction pump is measured to compare the permeation pressure of the membrane module with a predetermined value. When the permeation pressure of the module is restored to the predetermined value or less, the operation of the second air pump, the ultrasonic generator, the heating device and the stirrer is stopped, and the inlet pump, the suction pump and the first air pump are operated again. A method of cleaning a membrane separation apparatus for sewage treatment, further comprising the step. 11. The method according to any one of claims 8 to 10, wherein the plurality of ultrasonic generators are alternately arranged with a plurality of diffusers mounted under the membrane module. Cleaning method.

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